Calcium

Calcium ( /ˈkælsiəm/ kal-see-əm) is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust. Calcium is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate. Calcium is essential for living organisms, in particular in ... More

Mechanism of action:

Discovery Date:

  • 1808

Active moiety of:

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Also known as:

  • UN 1855,
  • Calcitat,
  • NA 1401,
  • Ca,
  • UN 1401,
  • Calcium, Ca

Chemistry

The 20th Element in the Periodic Table

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Potassium

Potassium ( /pɵˈtæsiəm/ po-tas-ee-əm) is the chemical element with the symbol K (from Neo-Latin kalium) and atomic number 19. Elemental potassium is...

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Scandium

Scandium ( /ˈskændiəm/ skan-dee-əm) is a chemical element with symbol Sc and atomic number 21. A silvery-white metallic transition metal, it has...

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Symbol:

  • Ca

Atomic mass:

Mass Uncertainty
  • 40.078 u (6.6551E-17 µg )
  • 0.004 u (6.64E-21 µg )

Electron affinity:

Value Uncertainty
  • 0.02455 eV (2.455E-8 MeV )
  • 0.0001 eV (1E-10 MeV )

Electronegativity (Pauling scale):

  • 1

Covalent radius:

  • 1.74 pm (6.85E-8 )

Van der Waals radius:

  • 240 pm (0.00000945 )

Melting Point:

  • 838.85 °C (1541.9 °F )

Boiling Point:

  • 1,483.85 °C (2702.96 °F )

Chemical series:

Periodic table block:

Ionization Energy:

  • 6.1132 eV (0.0000061132 MeV )

Discovering Country:

Electron Configuration:

  • Ar 4s2

Discoverer:

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